Die assemblies



Sept. 16, 1969 w. H. PHILLIPS, JR 3,466,922

DIE ASSEMBLIES Filed Nov. 30, 1967 2 Sheets-Sheet 1 46 h in g 4 'ji 1 5248 32 FIG. l

Ase-A .1? W 10 FIG. 2

r 4 mvsmon W 1; WILLIAM H. PHILLIPSJR BY7/&/ 3 ATTORNEYS Sept. 16, 1969w. H. PHILLIPS, JR 3,466,922

DIE ASSEMBLIES Filed Nov. 30, 1967 2 Sheets-Sheet 2 FIGB INVENTORWILLIAM H. PHILLIPS,JR.

Mew MM BW/ ATZRNEYS United States Patent 3,466,922 DIE ASSEMBLIESWilliam H. Phillips, Jr., North Bergen, N.J., assignor to Carmel:Company, Pittsburgh, Pa., a corporation of New Jersey Filed Nov. 30,1967, Ser. No. 686,904 Int. Cl. B2lc 3/00; B23b 31/12, /22 U.S. Cl.72-467 13 Claims ABSTRACT OF THE DISCLOSURE A die assembly having asplit holder or casing provided with a stepped longitudinal bore and adie insert disposed in the longitudinal bore in the holder or casing.The die insert is held solidly within the bore as a result of applying acompressive force upon the split casing for causing compressiveengagement of the bore surface with the die insert peripheral surfaceand by engaging a chordal transverse wedge with a flat surface on theperiphery of the die insert. The die insert is removed from the splitcasing by relieving the compressing force and by backing the wedgemember.

Background of the invention It is known to make drawing dies and thelike consisting of die inserts of cemented metal carbides and the likeassembled in a holder by means of either the so-called hot shrink methodor the cold press method. With die assemblies formed by either the hotshrink method or the cold press method, the assemblies are sold asunits, and when the die inserts are worn, the whole units are scrappedor the die inserts are ground to larger die openings for use for drawinglarger diameter workpieces.

In United States Letters Patent No. 3,109,663, issued Nov. 5, 1963 toWilliam H. Phillips, Jr., there is disclosed and claimed a demountabledie assembly comprising a holder adapted to maintain a die insert in anoperative position and permitting the removal of the die insert from theholder for replacement by a die insert of a different size or forreplacement with a new die insert when worn beyond acceptabletolerances. The holder is in the form of a split casing adapted tosupport a split removable annular spacer disposed in the holder forreceiving and supporting a cylindrical die insert made of refractorycemented metal carbide, or the like, the casing having means forapplying a compressive force to the split spacer for rigidly holding thedie insert in assembled position in the casing, and means for applying apositive force to spread the split casing so as to remove thecompressive force from the split spacer to permit the removal of the dieinsert and split spacer from the casing. The present invention providesan improvement on the invention in the above mentioned United StatesLetters Patent which permits omitting the split annular spacer byholding a die insert directly within a longitudinal bore in a splitholder or casing with one end of the die insert engaging a shoulderdisposed within the bore in the casing, and with a chordal transversewedge member having a flat surface arranged to engage a flat surface onthe periphery of the die insert. The die insert is thus held within thebore in the casing by the combined effect of a compressive force exertedupon the split casing causing a reduction of diameter of its die insertreceiving bore, and of the Wedging and locking action of the wedgemember. Additionally, the flat surface on the periphery of the dieinsert is in a plane inclined with respect to the axis of the dieassembly in an appropriate direction that causes the end of the dieinsert to be drawn against a shoulder in the holder internal bore whenthe wedge member is driven to its locking position.

The above mentioned objects and advantages of the invention, and furtherobjects and advantages thereof, will become apparent when the followingdescription of an illustrative example of a structure according to theprinciples of the invention is read in conjunction with the accompanyingdrawings wherein like numerals refer to like parts in the diverse viewsand in which:

Brief description of the drawings FIG. 1 is a top plan view, withportions broken away to show the internal construction, of a dieassembly embodying the features of the present invention, showing thedie insert in a released position;

FIG. 2 is a view similar to FIG. 1, but showing the die insert in alocked position;

FIG. 3 is a view in section from line 33 of FIG. 2;

FIG. 4 is a top elevation view of the die insert; and

FIG. 5 is a side elevation view thereof, substantially from line 55 ofFIG. 4.

Detailed description of a preferred embodiment Referring now to thedrawings, a die assembly according to the present invention, showngenerally at 10 in FIGS. l-3, comprises an outer supporting holder orcasing 12, made preferably of a metal such as steel and the like, havinga longitudinal bore 14 disposed for freely accepting a die insert 16made of cemented refractory metal carbide or the like. The longitudinalbore 14 in the holder or casing 12 is stepped in such manner as to beprovided with a decreased diameter end portion 18 forming an annularsupport shoulder 20 against which is normally engaged an end 22 of thedie insert 16, as best shown in FIG. 3. The example of die insert shownhas an internal sizing bore 24 for a workpiece, not shown, to be drawnthrough such die, a tapered entry surface 26 and an appropriate outletsurface 28. The diameter of the reduced diameter bore portion 18 of theholder or casing 12 is wide enough so as to afford appropriate clearancefrom the peripheral surface of the workpiece when the latter is drawnthrough the die. The casing 12 is provided with an appropriate truncatedentrance surface 30. The peripheral surface 32 of the die insert issubstantially cylindrical and of a diameter freely admitted within thelongitudinal bore 14 in the casing 12.

The casing 12 is split by being provided with a slot 34 longitudinallydisposed through a side wall thereof in a radial plane and thus definingsubstantially radially disposed opposed flat faces 36 and 38. It isobvious that slot 34 may be formed in a non-radial plane or,alternately, in a generally longitudinal plane at an angle with respectto a plane of symmetry of the casing 12. A pair of aligned bores 40 and42 having a common axis are disposed on a chord of the cylindricalcasing 12 adjacent the inner bore 14 thereof. Transverse chordal bore 46is internally threaded for accepting the threaded portion 44 of athreaded member or cap screw 46, while bore 42 has a smooth internalsurface for freely aceepting the body of the threaded member 46. Bore 42is provided with an enlarged diameter portion 48 proximate the peripheryof the casing 12 and forming an annular abutment surface or shoulder 50,such as to interfere with the enlarged head 52 of the threaded member orcap screw 46 presenting an annular abutment surface 54 adapted forengagement with the annular shoulder surface 50 when the threaded memberor bolt is appropriately drawn in.

Diametrically opposed to aligned bores 40 and 42 there is a chordaltransverse bore 56 disposed with its axis substantially parallel to theaxis of the aligned bores 40 and 42, such axis of the chordal transversebore 56 being substantially tangent to the inner bore 14 in the casing12, and the bore 56 being open to such inner bore 14.

Both ends of chordal transverse bore 56, proximate the periphery ofholder or casing 12 are internally threaded as shown at 58 and 60, andthe bore 56 is adapted to accept an elongated partly cylindrical wedgemember 62 having a wedging flat surface 64 disposed for engagement witha flat surface 66, also shown in FIGS. 4 and 5, on the peripheralsurface 32 of the die insert 16. The wedging fiat surface 64 on theelongated Wedge member 62 is disposed on a plane forming a slight angle,for example of the order of 1, with the longitudinal axis of theelongated wedge member, such that when the wedge member is displacedlongitudinally in bore 56 by way of the differential action of threadedplugs 68 and 70 disposed on the ends thereof in threaded portions 58 and60, respectively, of bore 56, the wedging flat surface 64 is caused tofirmly engage the flat surface 66 on the peripheral surface 32 of thedie insert 16.

As best shown in FIG. 3, the flat surface 66 on the peripheral surface32 of the die insert 16 is preferably in a plane forming a slight anglea of the order, for example, of /2", relatively to a generatrix of thecylindrical peripheral surface 32 of the die insert. Consequently, whenthe wedgmg flat surface 64 of elongated wedge member 62 is caused tofirmly engage the fiat surface 66 on the periphery of the die insertthere is generated upon the body of the die insert 16 a force that tendsto firmly apply the die insert annular end surface 22 with the casingannular shoulder 20.

As shown in FIG. 1, the die insert 16 is inserted in the longitudinalbore 14 of the holder or casing 12 with the threaded member or cap bolt46 backed off such that the annular abutting surface 54 of the bolt isdisengaged from the annular shoulder 50 between transverse bores 42 and48. Under such conditions the casing internal bore 14 has a diameterfreely accepting the die insert 16, and the elongated Wedge member 62being in the position indicated in FIG. 1 has its Wedging flat surface64 clear of the die insert flat surface 66. The only precaution forintroducing the die insert 16 in the bore 14 of the holder or casing 12is to properly align the fiat surface 66 on the peripheral surface 32 ofthe die insert substantially parallel to the axis of the chordaltransverse bore 56, the wedging flat surface 64 of elongated wedgemember 62 being oriented towards the internal bore 14 of the casing. Thedie insert 16 is inserted in the casing bore 14 such that the annularend surface of the die insert engages the abutment surface of annularshoulder 20.

The threaded member or cap bolt 46 is subsequently tightened to apply aslight compressive force upon the split casing 12 such that the surfaceof the bore 14 in the casing slightly engages the peripheral surface 32of the die insert 16. Threaded plug or set screw 70 is backed off, andthreaded plug or set screw 68 is advanced such that, the elongated wedgemember 62 is displaced towards the right, as seen in the drawing, to aposition such as shown in FIG. 2 wherein the wedging fiat surface 64 ofthe wedge member firmly engages the flat surface 66 on the periphery ofthe die insert 16 for proper locating and clamping of the die insertwithin the split casing 12 with the annular end surface 22 of the insertin abutting engagement with the annular shoulder 20 in the casing.Threaded member or cap bolt 46 is further advanced such as to applyfurther compressive force upon the split casing 12 by drawing closer toeach other the faces 36 and 38 of the slot 34, as shown in FIG. 2.

In order to remove the die insert 16, the preceding operation iseffected in a reverse order such that when the elongated wedge member 62has been displaced to the left to the position shown in FIG. 1, as aresult of threaded plug or set screw 64 being backed off and threadedplug or set screw 70 being advanced, with the threaded member or capscrew 46 backed off to the position shown, the compressive force appliedon the split casing 12 is relieved and the casing inner bore 14 springback to its original size, permitting the die insert to be slipped fromthe bore 14 in the casing for removal and replacement by another dieinsert. 7

Having thus described the invention by way of an illustrative example ofan embodiment incorporating the principles thereof, modificationswhereof will be apparent to those skilled in the art, what is sought tobe protected by United States Letters Patent is as follows:

I claim:

1. A die assembly comprising a support casing having a longitudinalcylindrical bore therethrough, a reduced diameter end portion in saidlongitudinal bore forming a shoulder, a longitudinally extending radialslot through a sidewall of said casing and defining a pair of opposedfaces, a removable cylindrical die insert disposed within thelongitudinal bore in said casing with an end thereof in abutment withsaid shoulder, a fiat surface on the periphery of said die insert, atransverse wedge member disposed substantially tangentially to said dieinsert and displaceable in a corresponding transverse bore in saidcasing for engagement with said flat surface and means for drawingtoward each other the faces of the slot in said casing.

2. The die assembly of claim 1 wherein the axis of said transverse boreis disposed substantially normal to a diameter of said die insertpassing through the slot in said casing.

3. The die assembly of claim 1 wherein said wedge member has alongitudinally disposed flat surface at a slight angle to the axisthereof and the flat surface on the periphery of said die insert is in aplane disposed at a slight angle to the longitudinal axis of said insertfor urging said insert with the end thereof in abutting engagement withthe shoulder in said casing when the fiat surface of said wedge memberis engaged with said flat surface on the periphery of said die insert.

4. The die assembly of claim 1 wherein the means for drawing toward eachother the faces of the slot in said casing comprises a pair of alignedbores extending in opposite directions from the faces of said slot, oneof said bores being threaded for accepting a threaded member having anenlarged head and the other of said bores having an enlarged shoulderforming portion communicating with the exterior of said casing, and athreaded member disposed in said aligned bores in threaded engagementwith the threaded one of said bores, said threaded member having anenlarged head adapted for engagement with the shoulder in the other borefor drawing the faces of said slot toward each other.

5. The die assembly of claim 1 wherein the means for axially displacingthe wedge member comprises a pair of threaded plug members each disposedin an internally threaded end portion of said transverse bore on an endof said wedge member.

6. A die assembly comprising a support casing having a'longitudinalstepped bore therethrough for defining a supporting shoulder therein, alongitudinally extending slot through a sidewall of said casing anddefining a pair of opposed faces, a removable cylindrical die insertdisposed within the longitudinal bore in said casing with an end thereofin abutting engagement with said supporting shoulder, a flat surface onthe periphery of said die insert, a chordal transverse bore through saidcasing having an axis substantially tangent to the longitudinal bore insaid casing and open to said longitudinal bore, an axially displaceableelongated wedge member disposed in said transverse bore, said wedgemember having an inclined flat surface disposed for engagement with theflat surface on the periphery of said die insert, means for drawingtoward each other the faces of the slot in said casing and means foraxially displacing said wedge member for engagement of the inclined flatsurface thereof with the flat surface on the periphery of said dieinsert.

7. The die assembly of claim 6 wherein the axis of said chordaltransverse bore is disposed substantially normal to a diameter of saiddie insert passing through the slot in said casing.

8. The die assembly of claim 6 wherein the flat surface on the peripheryof said die insert is in plane disposed at a small angle to thelongitudinal axis of said insert for urging said insert with the endthereof in abutting engagement with the supporting shoulder in saidcasing when the inclined flat surface of said wedge member is inengagement with said fiat surface on the periphery of said die insert.

9. The die assembly of claim 6 wherein the means for drawing toward eachother the faces of the slot in said casing comprises a pair of alignedbores extending in opposite directions from the faces of said slot, oneof said bores being threaded and the other having an enlarged shoulderforming portion communicating with the exterior of said casing and athreaded member disposed in said aligned bores in threaded engagementwith the threaded one of said bores, said threaded member having anenlarged head adapted for engagement with the shoulder in the other borefor drawing the faces of said slot toward each other.

10. The die assembly of claim 6 wherein the means for axially displacingthe wedge member comprises a pair of threaded plug members each disposedin an internally threaded end portion of said chordal transverse bore onan edge of said wedge member.

11. The die assembly of claim 7 wherein the means for drawing towardeach other the faces of the slot in said casing comprises a pair ofaligned bores extending in opposite directions from the faces of saidslot, one of said bores being threaded and the other having an en largedshoulder forming portion communicating with the exterior of said casingand a threaded member disposed in said aligned bores in threadedengagement with the threaded one of said bores, said threaded memberhaving an enlarged head adapted for engagement with the shoulder in theother bore for drawing the faces of said slot toward each other.

12. The die assembly of claim 11 wherein the means for axiallydisplacing the wedge member comprises a pair of threaded plug memberseach disposed in an internally threaded end portion of said chordaltransverse bore on an end of said wedge member.

13. The die assembly of claim 12 wherein the flat surface on theperiphery of said die insert is in a plane disposed at a small angle tothe longitudinal axis of said insert for urging said insert with the endthereof in abutting engagement with the supporting shoulder in saidcasing when the inclined fiat surface of said wedge member is engagedwith said flat surface on the periphery of said die insert.

References Cited UNITED STATES PATENTS 3,091,474 5/1963 Boutros et al.287-5209 XR 3,109,663 11/ 1963 Phillips 279-41 3,191,374 6/1965 Ege279-467 XR ROBERT C. RIORDON, Primary Examiner D. D. EVENSON, AssistantExaminer US. Cl. X.R. 279-41; 287-5209

